When Sigmund Freud entered upon the psychoanalytic road he saw among the then prevailing systems of psychology none by which his work could have been truly furthered and no particular philosophy which could have served him as a point of departure. The abundance and complexity of the material demand the positing of new, secondary propositions which, because of the growth of the investigated field, soon become main propositions; but always one can demonstrate, even though in round-about ways, this dependence of Freudian psychoanalysis on the fundamental proposition of psychic determinism. The reason that Baruch Spinoza’s psychology is important for psychoanalysis and is, indeed, in these points rather close to it – is that it regards mental phenomena as lawfully determined and the processes of imagining and remembering as anything but mere copying and registering, but rather as a creative struggle for life and self-preservation.